Myth: "You MUST avoid failing to file taxes at the time required by law."
Phony tax preparers may offer extravagant services through alleged clever use of the law. Watch out for such enticing claims. The IRS considers a taxpayer, not preparer, liable for false statements or mistakes on tax documents. Fortunately, there are several ways to ensure a tax prep service is legitimate.
Back taxes are simply taxes that you owe that you didn't pay when they were due. If you've underpaid taxes for any reason, the balance that you owe is considered back tax. You may have failed to report taxable income (intentionally or unintentionally, it doesn't matter) – as the IRS sees it...you still owe them money in the form of a back tax.